/* ============================================================
   MEDIPREDICT AI — DESIGN SYSTEM
   Medical Healthcare SaaS — Full Rebuild
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

/* ---- CSS Variables (Light Mode) ---- */
:root {
  /* Brand */
  --color-primary:        #1a7fe4;
  --color-primary-dark:   #1260b8;
  --color-primary-light:  #e8f3ff;
  --color-primary-glow:   rgba(26,127,228,0.18);

  /* Accent */
  --color-success:        #0fba81;
  --color-success-light:  #e6faf4;
  --color-danger:         #e53935;
  --color-danger-light:   #fff0f0;
  --color-warning:        #f59e0b;
  --color-warning-light:  #fffbeb;

  /* Surface */
  --bg-body:     #f0f4f8;
  --bg-surface:  #ffffff;
  --bg-muted:    #f8fafc;
  --bg-inset:    #f1f5f9;

  /* Border */
  --border-base:  #e2e8f0;
  --border-focus: var(--color-primary);

  /* Text */
  --text-heading:  #0f1c2e;
  --text-body:     #374151;
  --text-muted:    #64748b;
  --text-on-accent: #ffffff;

  /* Shadows */
  --shadow-xs:  0 1px 2px rgba(15,28,46,0.06);
  --shadow-sm:  0 2px 6px rgba(15,28,46,0.08);
  --shadow-md:  0 4px 16px rgba(15,28,46,0.10);
  --shadow-lg:  0 8px 32px rgba(15,28,46,0.12);
  --shadow-xl:  0 16px 48px rgba(15,28,46,0.14);

  /* Shape */
  --radius-sm:  8px;
  --radius-md:  12px;
  --radius-lg:  16px;
  --radius-xl:  24px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast:   0.15s ease;
  --transition-base:   0.25s ease;
  --transition-slow:   0.4s ease;

  /* Navbar */
  --nav-bg: rgba(255,255,255,0.92);
  --nav-border: rgba(226,232,240,0.8);
}

/* ---- Dark Mode Overrides ---- */
.dark-theme {
  --color-primary:        #4fa8f5;
  --color-primary-dark:   #2183d8;
  --color-primary-light:  #0d1e38;
  --color-primary-glow:   rgba(79,168,245,0.20);

  --color-success:        #34d399;
  --color-success-light:  #062a1e;
  --color-danger:         #f87171;
  --color-danger-light:   #2a0a0a;
  --color-warning:        #fbbf24;
  --color-warning-light:  #2d1f04;

  --bg-body:     #080e1a;
  --bg-surface:  #0f1825;
  --bg-muted:    #131d2e;
  --bg-inset:    #192336;

  --border-base:  #1e2d42;
  --border-focus: var(--color-primary);

  --text-heading:  #e8f0fb;
  --text-body:     #94a3b8;
  --text-muted:    #4e6280;
  --text-on-accent: #ffffff;

  --shadow-xs:  0 1px 2px rgba(0,0,0,0.4);
  --shadow-sm:  0 2px 6px rgba(0,0,0,0.5);
  --shadow-md:  0 4px 16px rgba(0,0,0,0.6);
  --shadow-lg:  0 8px 32px rgba(0,0,0,0.7);
  --shadow-xl:  0 16px 48px rgba(0,0,0,0.8);

  --nav-bg: rgba(8,14,26,0.92);
  --nav-border: rgba(30,45,66,0.9);
}

/* ---- Reset & Base ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background-color: var(--bg-body);
  color: var(--text-body);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  line-height: 1.6;
  transition: background-color var(--transition-slow), color var(--transition-slow);
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }

/* ---- Typography ---- */
h1, h2, h3, h4, h5 {
  color: var(--text-heading);
  font-weight: 700;
  line-height: 1.2;
  transition: color var(--transition-slow);
}
h1 { font-size: clamp(2rem, 5vw, 3.25rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2rem); }
h3 { font-size: 1.25rem; }
h4 { font-size: 1rem; }

p { color: var(--text-body); transition: color var(--transition-slow); }

/* ---- Navbar ---- */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--nav-bg);
  border-bottom: 1px solid var(--nav-border);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  padding: 0 2rem;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  transition: background var(--transition-slow), border-color var(--transition-slow);
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  text-decoration: none;
}

.navbar-brand-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  box-shadow: 0 2px 8px var(--color-primary-glow);
}

.navbar-brand-icon svg {
  width: 20px;
  height: 20px;
  color: #fff;
}

.navbar-brand-name {
  font-size: 1.125rem;
  font-weight: 800;
  color: var(--text-heading);
  transition: color var(--transition-slow);
}

.navbar-brand-name span {
  color: var(--color-primary);
}

.navbar-right {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* Back Button */
.btn-back {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
  padding: 0.5rem 0.875rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-base);
  background: var(--bg-surface);
  box-shadow: var(--shadow-xs);
  transition: all var(--transition-fast);
}
.btn-back:hover {
  color: var(--color-primary);
  border-color: var(--color-primary);
  background: var(--color-primary-light);
  transform: translateX(-2px);
}
.btn-back svg { width: 16px; height: 16px; transition: transform var(--transition-fast); }
.btn-back:hover svg { transform: translateX(-2px); }

/* Theme Toggle Switch */
.theme-switch-wrap {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-muted);
}
.theme-switch {
  position: relative;
  width: 44px;
  height: 24px;
  flex-shrink: 0;
}
.theme-switch input {
  opacity: 0;
  width: 0;
  height: 0;
  position: absolute;
}
.theme-switch-track {
  position: absolute;
  inset: 0;
  border-radius: var(--radius-full);
  background: var(--border-base);
  transition: background var(--transition-base);
  cursor: pointer;
}
.theme-switch input:checked + .theme-switch-track {
  background: var(--color-primary);
}
.theme-switch-thumb {
  position: absolute;
  top: 3px;
  left: 3px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: #fff;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-base);
  pointer-events: none;
  display: flex;
  align-items: center;
  justify-content: center;
}
.theme-switch input:checked ~ .theme-switch-thumb {
  transform: translateX(20px);
}
.theme-switch-thumb svg { width: 10px; height: 10px; color: var(--color-primary); }

/* ---- Surface Cards ---- */
.card {
  background: var(--bg-surface);
  border: 1px solid var(--border-base);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: background var(--transition-slow), border-color var(--transition-slow), box-shadow var(--transition-base);
  overflow: hidden;
}
.card-hover:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
  border-color: var(--color-primary);
}
.card-body { padding: 1.75rem; }
.card-body-lg { padding: 2.5rem; }

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: inherit;
  font-weight: 600;
  font-size: 0.9375rem;
  border-radius: var(--radius-md);
  padding: 0.75rem 1.5rem;
  transition: all var(--transition-fast);
  cursor: pointer;
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
  box-shadow: 0 4px 12px var(--color-primary-glow);
}
.btn-primary:hover:not(:disabled) {
  background: var(--color-primary-dark);
  box-shadow: 0 6px 18px var(--color-primary-glow);
  transform: translateY(-1px);
}
.btn-primary:active:not(:disabled) { transform: translateY(0); }
.btn-primary:disabled {
  opacity: 0.45;
  cursor: not-allowed;
  box-shadow: none;
  transform: none;
}

.btn-ghost {
  background: transparent;
  color: var(--text-body);
  border-color: var(--border-base);
}
.btn-ghost:hover:not(:disabled) {
  background: var(--bg-inset);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.btn-lg { padding: 0.9rem 2rem; font-size: 1rem; border-radius: var(--radius-lg); }
.btn-full { width: 100%; }

/* ---- Form Components ---- */
.form-section {
  padding: 1.75rem;
  border-bottom: 1px solid var(--border-base);
  transition: border-color var(--transition-slow);
}
.form-section:last-child { border-bottom: none; }
.form-section-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}
.form-section-badge {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-primary-light);
  color: var(--color-primary);
  font-size: 0.75rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: background var(--transition-slow), color var(--transition-slow);
}
.form-section-title {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-heading);
  transition: color var(--transition-slow);
}

.form-grid { display: grid; gap: 1.25rem; }
.form-grid-2 { grid-template-columns: repeat(2, 1fr); }
.form-grid-3 { grid-template-columns: repeat(3, 1fr); }
@media (max-width: 768px) {
  .form-grid-2, .form-grid-3 { grid-template-columns: 1fr; }
}
@media (min-width: 768px) and (max-width: 1024px) {
  .form-grid-3 { grid-template-columns: repeat(2, 1fr); }
}

.form-group { display: flex; flex-direction: column; gap: 0.375rem; }

.form-label {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-muted);
  letter-spacing: 0.01em;
  transition: color var(--transition-slow);
}

.form-control {
  width: 100%;
  padding: 0.6875rem 0.875rem;
  font-family: inherit;
  font-size: 0.9375rem;
  font-weight: 400;
  color: var(--text-heading);
  background: var(--bg-muted);
  border: 1.5px solid var(--border-base);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  outline: none;
  appearance: none;
}
.form-control::placeholder { color: var(--text-muted); opacity: 0.6; }
.form-control:focus {
  border-color: var(--color-primary);
  background: var(--bg-surface);
  box-shadow: 0 0 0 3px var(--color-primary-glow);
}
.form-control.is-valid { border-color: var(--color-success); }
.form-control.is-invalid { border-color: var(--color-danger); }
.form-control:disabled, .form-control[readonly] {
  opacity: 0.65;
  cursor: not-allowed;
  background: var(--bg-inset);
}

select.form-control {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3E%3Cpath stroke='%2364748b' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='M6 8l4 4 4-4'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  background-size: 1.25rem;
  padding-right: 2.5rem;
}

.form-hint {
  font-size: 0.75rem;
  color: var(--text-muted);
}
.form-error {
  font-size: 0.75rem;
  color: var(--color-danger);
  display: none;
}
.form-group.has-error .form-error { display: block; }
.form-group.has-error .form-control { border-color: var(--color-danger); }

/* BMI badge */
.bmi-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.8125rem;
  font-weight: 600;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  background: var(--color-primary-light);
  color: var(--color-primary);
  transition: all var(--transition-base);
}

/* ---- Alert / Banner ---- */
.alert {
  display: flex;
  align-items: flex-start;
  gap: 0.875rem;
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  border: 1px solid;
  font-size: 0.875rem;
  line-height: 1.5;
}
.alert-warning {
  background: var(--color-warning-light);
  border-color: var(--color-warning);
  color: #92400e;
}
.dark-theme .alert-warning { color: #fbbf24; }
.alert-icon {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  margin-top: 1px;
  color: var(--color-warning);
}
.alert-banner {
  border-radius: 0;
  border-left: none;
  border-right: none;
  border-top: none;
}

/* ---- Page Wrapper ---- */
main { flex: 1; }
.page-wrapper { max-width: 1100px; margin: 0 auto; padding: 2.5rem 1.5rem; }
.page-wrapper-sm { max-width: 760px; margin: 0 auto; padding: 2.5rem 1.5rem; }

/* ---- Page Header ---- */
.page-header { margin-bottom: 2rem; }
.page-header-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-primary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.625rem;
}
.page-header-kicker-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-primary);
  animation: pulse-dot 2s infinite;
}
@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.7); }
}
.page-header h1 { margin-bottom: 0.625rem; }
.page-header p { color: var(--text-muted); max-width: 560px; }

/* ---- Footer ---- */
.footer {
  padding: 1.5rem 2rem;
  text-align: center;
  font-size: 0.8125rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-base);
  transition: border-color var(--transition-slow);
}

/* ---- Status Pill ---- */
.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 600;
}
.status-pill-dot { width: 6px; height: 6px; border-radius: 50%; }
.status-pill-online { background: var(--color-success-light); color: var(--color-success); }
.status-pill-online .status-pill-dot { background: var(--color-success); animation: pulse-dot 2s infinite; }
.status-pill-pending { background: var(--color-warning-light); color: var(--color-warning); }
.dark-theme .status-pill-pending { color: var(--color-warning); }
.status-pill-pending .status-pill-dot { background: var(--color-warning); }

/* ---- Animations ---- */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}
.animate-fade-up { animation: fadeUp 0.5s ease both; }
.animate-delay-1 { animation-delay: 0.1s; }
.animate-delay-2 { animation-delay: 0.2s; }
.animate-delay-3 { animation-delay: 0.3s; }
.animate-delay-4 { animation-delay: 0.4s; }

/* ---- Form Footer ---- */
.form-footer {
  padding: 1.5rem 1.75rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  border-top: 1px solid var(--border-base);
  background: var(--bg-muted);
  flex-wrap: wrap;
  transition: background var(--transition-slow), border-color var(--transition-slow);
}
.form-footer-hint {
  font-size: 0.8125rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.375rem;
}

/* ---- Divider ---- */
.divider {
  height: 1px;
  background: var(--border-base);
  margin: 1.5rem 0;
  transition: background var(--transition-slow);
}

/* Spinner */
@keyframes spin { to { transform: rotate(360deg); } }
.spinner {
  display: inline-block;
  width: 18px;
  height: 18px;
  border: 2.5px solid rgba(255,255,255,0.35);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

/* ---- Utility ---- */
.hidden { display: none !important; }
.text-muted { color: var(--text-muted); }
.text-primary { color: var(--color-primary); }
.text-success { color: var(--color-success); }
.text-danger { color: var(--color-danger); }

/* ---- Responsive Navbar ---- */
@media (max-width: 600px) {
  .navbar { padding: 0 1rem; }
  .theme-switch-wrap .theme-label { display: none; }
}